The “Cough Trick” Reduces Pain During Removal of Closed-suction Drains after Total Knee Arthroplasty: A Randomized Trial

Background

Drain removal after TKA can be painful. Prior research suggests that the “cough trick,” in which a patient coughs at the same time she or he receives an injection, effectively decreases pain. To our knowledge, this intervention has not been evaluated as a way to reduce pain during other brief but painful interventions, such as removal of closed-suction drains after orthopaedic surgery.

Question/purpose

Does the cough trick reduce pain while a surgeon is removing a closed-suction drain after TKA?

Methods

Fifty-six patients with primary osteoarthritis who underwent primary TKA were randomized into two groups: drain removal as the patient coughed (n = 28 patients; three men, 25 women) or drain removal using the usual process, without the cough trick (n = 28 patients; three men, 25 women). The study groups were not different in terms of gender, BMI, surgical time, or other baseline variables, and other than the addition of the cough trick, there were no differences in surgical treatment or other elements of aftercare. Likewise, at baseline, the verbal numeric rating scale (VNRS) score for pain before the drain was removed was not different between the groups (3.1 ± 1.7 versus 3.3 ± 1.3; p = 0.72). The level of pain before and during drain removal was recorded using a VNRS by an orthopaedic surgeon who was not involved in the care of the study patients. We considered the minimum clinically important difference on the 10-point scale to be 2 points, based on prior evidence.

Results

The mean ± SD VNRS for the pain level during drain removal was lower in the cough trick group than that in the control group (1.6 ± 1.0 versus 3.7 ± 1.9, mean difference 2.1; 95% CI, 1.3-2.9; p < 0.001).

Conclusions

The cough trick during removal of a closed-suction drain tube in patients undergoing TKA reduced the level of pain in this small randomized trial. We suggest that surgeons consider this technique when removing drains after TKA because it is a noninvasive technique and it is easy to perform. Because the cough trick has been shown by others to be effective at reducing pain during venipuncture and parenteral injections, and we found it was effective for that purpose during drain removal after TKA, we believe this finding probably generalizes well to most minor procedures that cause transient, sharp pain. We suggest that it could be used to make such procedures more comfortable for patients, as well as for drain removal in other types of surgery where drains still are commonly used (including spine surgery and tumor surgery).

Level of Evidence

Level I, therapeutic study.